名词 life-time:

1. the period during which something is functional (as between birth and death)

lifepak手提式心脏除颤器(商品名)lifen.一生；生命；生活；人生lifecycle model生命周期模型life-of-mann.美木life conditions生活状况life-oriented生活化life cycle form生活史型life technology生命技术life and health生命与健康life assistance生活救助life dreariness人生悲凉感life trajectory生活轨迹

1. A temporary structure erected within a planned urban area must be demolished within the approved period of time for its use.
   在城市规划区内进行临时建设，必须在批准的使用期限内拆除。
2. The disk space required by a snapshot depends on how many different pages in the source database are updated during the life of the snapshot.
   快照所需的磁盘空间取决于在快照使用期限内源数据库中更新的不同页的数量。
3. The machine's life is very long.
   这机器使用寿命很长。
4. Women have a higher life expectancy than men.
   女人比男人的预期寿命长。